Variation in Hospital Practices Regarding Marijuana Use in Pregnancy and Lactation

Abstract

Background and Objectives:

Evidence is lacking on the safety of marijuana (MJ) exposure on the fetus and neonate, and current guidelines vary across professional organizations. We examined variation in hospital practices regarding use of mother's own milk (MOM) in the setting of perinatal MJ exposure based on hospital location and state MJ legal designation.

Methods:

We conducted a cross-sectional electronic survey of U.S. perinatal health care workers on hospital policies and clinical practice regarding maternal MJ use from November 2021 to April 2022. We analyzed responses from those working in states with legal recreational MJ (REC), MJ legal for medical use only (MED), and illegal MJ (NON), based on legalization status as of 2021.

Results:

Two thousand six hundred eighty-three surveys were analyzed from 50 states and the District of Columbia, with 1,392 respondents from REC states, 524 from NON states, and 668 from MED states. Hospital policies and practices showed significant differences between facilities from REC and NON states. REC states were more likely to have policies allowing use of MOM from mothers using MJ after delivery and less likely to routinely include cannabinoids in toxicology testing. Hospital policies also varied within individual hospitals between well baby nurseries and neonatal intensive care units.

Conclusions:

Hospital practices vary widely surrounding provision of MOM in the presence of maternal MJ use, based on state legalization status and hospital unit of care. Clear guidelines across professional organizations regarding perinatal MJ exposure, regardless of legality, are warranted to improve consistency of care and patient education.

Introduction

As of 2022, recreational use of marijuana (MJ) by adults is now legal in 16 U.S. states and the District of Columbia and an additional 18 states allow medicinal use of MJ (Fig. 1).^1,2 With broader legalization, MJ use has increased in the peripartum period in the past decade,^3,4 Between 2002 and 2014, self-reported MJ use in pregnant people increased by 62%.⁵ Nearly half of mothers using MJ prepregnancy continue to use MJ during pregnancy.⁶ MJ is now the most used recreational drug among lactating women.⁷ As MJ has been legalized in additional states, the perception of risk has shifted, with increasing maternal perceptions of regular use of MJ having no risk of harm to the developing fetus and neonate.⁸

FIG. 1.

Changes in marijuana legalization from 2010 to 2022: (A) 2010; (B) 2015; (C) 2020; (D) 2022. Black states represent marijuana legal for recreational use; gray states represent marijuana legal for medical use; white states represent marijuana not legal for use.

Infant feeding with mother's own milk (MOM) is recommended by multiple professional organizations with few contraindications.^9–11 Multiple studies have demonstrated the presence in human milk of Δ-9-tetrahydrocannabinol (THC), the primary psychoactive component of MJ, from women using MJ.^12–16 The level of THC has been shown to be concentrated in human milk relative to plasma,^14,15 consistent with the accumulation of THC in milk due to its lipophilic properties. The duration of THC in MOM after use has been difficult to quantify due to its complex metabolism, variability in fat content of human milk, and variations in frequency and potency.^12,14,16 In addition, recent investigations have demonstrated continued or an increase in maternal MJ use postpartum.^4,14,17,18

The long-term effects of prolonged THC exposure to infants via MOM is uncertain, however, animal studies and emerging retrospective studies to date have shown negative developmental and behavioral outcomes among children exposed to MJ in the perinatal period.^7,17–25

In the setting of evidence gaps to inform clinical guidance regarding lactation and MJ use, as well as a large increase in MJ use during lactation in the past decade, professional organizations have published varied recommendations. For instance, the 2012 guideline from the American Academy of Pediatrics (AAP) stated MJ use as a contraindication to breastfeeding,²⁶ and as of 2022, this recommendation has shifted to discouraging the use of MJ while breastfeeding.²⁷ Similarly, the American College of Obstetricians and Gynecologists (ACOG) recommends discouraging the use of MJ during both pregnancy and breastfeeding.²⁸ The Academy of Breastfeeding Medicine recommends caution with heavy use (without defining heavy use), but does not clearly discourage breastfeeding in the setting of ongoing MJ use.²⁹ The differences in the recommendations from these three major organizations, while nuanced, may affect providers' interpretations of the best practice in this area, although this has not been rigorously examined.

Use of hospital-based perinatal practice guidelines to coordinate consistent patient care across providers and services is routine in well baby nurseries and neonatal intensive care units (NICUs). For example, lactation-support guidelines typically include criteria for specific maternal conditions when provision of MOM may be contraindicated or discouraged. There are no studies to our knowledge examining the content of perinatal hospital guidelines focused on lactation support practices for mothers using MJ. A deeper understanding of such hospital practices in the setting of the changing landscape of MJ legalization across the United States and mixed professional organization guidance may be helpful to inform policy makers, researchers, and local hospital teams working to develop their own guidelines. Recognizing this research gap, we conducted a cross-sectional survey of U.S. perinatal hospital providers to examine (1) variation in hospital-based practices related to lactation and maternal MJ use and (2) differences in such practices according to location in states with and without recreational legalization of MJ.

Materials and Methods

Study participants

The survey target population was health care providers providing care to pregnant and lactating patients and newborns in hospitals within the United States, including attending physicians, advanced practice providers, nurses, and lactation consultants. An anonymous electronic survey was distributed via e-mail and listservs obtained through membership within professional organizations representing perinatal providers. Members were invited to respond to the survey if they currently worked in a hospital providing care to pregnant or lactating people or to newborns and were asked to respond regarding hospital practices in the hospital where they worked the most. Survey participation was voluntary, with completion of survey serving as consent for participation. Estimated time for completion of the survey was 15–20 minutes. A $10 Amazon gift card was offered as an incentive to the first 200 respondents.

Survey tool

The REDCap survey³⁰ was distributed to groups of interest from November 16, 2021, to April 26, 2022. Survey content is available in Appendix Table A1. Questions included demographic data; location of the hospital that the respondent worked at most; information on hospital-based practices regarding maternal MJ use. Data gathered regarding hospital practices included criteria for provision of MOM in the NICU and Level 1 nursery with maternal MJ use, policies on toxicology testing, and influence of timing of MJ use on provision of MOM. A group of board-certified neonatologists, board-certified obstetricians, neonatal nurses, and lactation consultants reviewed the content and construct validity of the survey items. Pilot testing of the survey was performed for readability, clarity, and functionality before finalization and distribution.

This study used a cross-section survey design and was approved by the Baystate Medical Center Institutional Review Board.

Measures

We categorized survey respondents' hospital location by state MJ legalization status according to laws in effect at the time of the survey (2021). Respondents from states with recent legalization of MJ that overlapped survey design and data collection were excluded only from the specific analysis of state legal designation (Alabama, South Dakota, and Virginia; N = 99). We categorized hospitals as those located in a state that had legalized recreational MJ use (REC), those located in a state with MJ legal for medical use only (MED), and those located in states where MJ was illegal (NON) according to laws in existence at the time of survey. For this study, MJ was considered illegal if only cannabidiol with limited or no THC content is legalized in that particular state.

Statistical analysis

We summarized hospital-based practices using descriptive statistics with frequency distributions and percentages. Data were analyzed in Stata (17.0; StataCorp, LLC, College Station, TX) and MS Excel. Because of the large number of responses, many group differences, although trivial, would be statistically significant. To avoid reporting trivial results as significant, we considered a 10 percentage-point difference in a comparison of groups as interesting and notable. Moreover, at 10 percentage-point, the difference would be statistically significant at p = 0.05, regardless of what group proportions were being compared, as long as there were at least 500 responses per group in the comparison.

Results

The survey was distributed to groups of interest as shown in Table 1, with a total of 2,683 completed surveys. Hospital demographics of respondents are shown in Table 2. Overall, 1,298 (48.4%) reported providing neonatal care; 721 (26.9%) providing obstetric care; and 665 (24.8%) providing both obstetric and neonatal care. We found that 11.8% of respondents worked in hospitals with only a Level 1 nursery, 68.1% worked in hospitals with only an NICU, and 20.2% worked in hospitals with both an NICU and a Level 1 nursery.

Table 1.

Perinatal Professional Organizations and Distribution Methods with Approximate Membership of Groups of Interest

Group	Approximate membership	Method of distribution
AAP Section on Breastfeeding	710	E-mail listserv
AAP Section on Neonatal-Perinatal Medicine	4,445	E-mail listserv
American College of Nurse-Midwives	6,500	E-mail listserv
International Lactation Consultant Association	820	E-mail
Obstetrician-Gynecologists, publicly available e-mails	290	E-mail
National Association of Neonatal Nurses	7,500	Electronic message board, e-mail newsletter
Society of Maternal Fetal Medicine	5,500	Electronic message board
Society for Physician Assistants in Pediatrics	1,200	E-mail listserv
United States Lactation Consultant Association	2,300	Electronic newsletter

Survey was distributed via e-mail listserv, direct e-mail, posting on electronic message board, or included in e-mail newsletter. Varied methods of distribution were based on individual group requirements.

AAP, American Academy of Pediatrics.

Table 2.

Hospital Demographics Reported by Survey Respondents

Demographics	N = 2,683, N (%)
Location of primary practice site
Urban	1,705 (63.5)
Suburban	783 (29.2)
Rural	188 (7.0)
Other	7 (0.003)
Patient population of practice site
Adults only	135 (5.0)
Adults and neonates	1,311 (48.9)
Adults, pediatric patients, and neonates	967 (36.0)
Pediatric patients and neonates only	270 (10.1)
Highest level of neonatal care
Level 1	315 (11.7)
Level 2	889 (33.1)
Level 3	969 (36.1)
Level 4	510 (19.0)

Levels of neonatal care are based on AAP designation.³¹

AAP, American Academy of Pediatrics.

Of all respondents, 63.8% reported that cannabinoids are always included in maternal toxicology screens, and 62.9% reported that cannabinoids are always included in infant toxicology screening for patients in the NICU and Level 1 nursery. Of respondents from REC states, 60.1% reported that cannabinoids were always included in maternal toxicology screening, compared with 68.9% of respondents from NON states and 67.7% of respondents from MED states. For infant toxicology screens, 60.7% of respondents from REC states, 60.8% of respondents from MED states, and 70.2% of respondents from NON states reported that cannabinoids are always included.

Regarding infant screening toxicology testing, urine toxicology was most commonly used (70.8%), with meconium, umbilical cord, and hair testing less commonly used (62.7%, 48.9%, and 27.3%). Of respondents who indicated that their hospital utilized urine toxicology screening for newborns, 57.8% reported using another method in addition to urine for testing. For urine toxicology testing of pregnant or postpartum patients, 52.4% of respondents indicated that their hospital required written consent for screening, and 26.4% required verbal consent (Table 3). A total of 13.6% reported that neither verbal nor written consent was required, with 7.7% of respondents indicating that they were uncertain of requirements. Respondents from REC states were more likely to require consent than MED or NON (89.1 versus 73.7% or 80.5%, respectively).

Table 3.

Responses by State Legality for Neonatal Intensive Care Unit Policies on Use of Mother's Own Milk with Marijuana Use in Pregnancy or Lactation

MJ legality	NICU policy in place (%)	Allow MOM with MJ use in pregnancy (%)		Require negative toxicology screen to provide MOM (%)	Require abstention from MJ to provide MOM (%)	Require consent for toxicology screening	Cannabinoids always included in toxicology screening (%)
MJ legality	NICU policy in place (%)	Any time	Ongoing	Require negative toxicology screen to provide MOM (%)	Require abstention from MJ to provide MOM (%)	Require consent for toxicology screening	Maternal	Infant
All states (2,683)	1,392/2,338 (59.5)	916/1,129 (81.1)	532/1,122 (47.4)	642/910 (70.5)	676/911 (74.2)	2,112/2,683 (78.7)	1,713/2,683 (63.8)	1,685/2,683 (62.8)
REC (1,392)	681/1,185 (57.5)	459/555 (82.7)	298/552 (54.0)	325/457 (71.1)	348/455 (76.5)	1,154/1,392 (82.9)	836/1,392 (60.1)	845/1,392 (60.7)
MED (668)	363/597 (60.8)	242/299 (80.9)	117/297 (39.4)	158/240 (65.8)	169/241 (70.1)	492/668 (73.7)	452/668 (67.7)	406/668 (60.8)
NON (524)	290/474 (61.2)	189/233 (81.1)	103/230 (44.8)	137/187 (73.3)	143/189 (75.7)	383/524 (73.1)	361/524 (68.9)	368/524 (70.2)

Respondents from Virginia, South Dakota, and Alabama (N = 99) were excluded from categorized groups due to legislation changes within the past 3 years (N = 99). State legal status and number of respondents are available in Appendix Table A2.

MED, medical use only; MJ, marijuana; MOM, mother's own milk; NICU, neonatal intensive care unit; NON, illegal MJ use; REC, legalized recreational MJ use.

Among the 2,367 respondents with an NICU in their institution, 59.5% of respondents reported that the NICU had a policy in place regarding use of MOM among infants whose mothers used MJ, while 29.0% reported that their NICU had no policy (Table 3). Respondents from REC states were the least likely to report a policy in place in their NICU (57.5%), while respondents from MED states were similar to respondents from NON states (60.8% and 61.2%, respectively). Respondents from REC, MED, and NON states were similar in whether their NICU policies allowed use of MOM in the setting of MJ use at any time during pregnancy (82.7% versus 80.9% versus 81.1%), although some respondents reported conditions that must be met before use.

Of those respondents with an NICU policy in place, 70.5% reported that a negative maternal urine toxicology screen for MJ was required before use of MOM, without significant difference between respondents from REC, MED, and NON states. Respondents varied in the number of negative MJ toxicology screens required, with 46.4% requiring one negative screen, 43.8% requiring two negative screens, and 9.8% requiring more than two screens. Verbal commitment of abstention from MJ was required before use of MOM by 74.2% of respondents; of those, 12% requiring 1 week of abstention, 29.8% requiring 2 weeks, and 42.7% requiring more than 2 weeks of abstention from MJ. In addition, 13.6% of respondents required abstention from MJ but did not specify a period of time, and 12 respondents (1.8%) indicated other lengths of time, ranging from 2 to 80 days.

If continued MJ use was reported after delivery, only 47.4% of respondents reported that their NICU policy allowed use of MOM, with 66.1% requiring a signed acknowledgment of risk for use of MOM with ongoing MJ use. Respondents from REC states reported the most permissive NICU policies with recent and ongoing use of MJ: 75.1% of reported policies allowed use of MOM with recent MJ use, as defined by each unit, and 54% allowed use of MOM with ongoing MJ use. NON and MED states reported more restrictive NICU policies in these situations, with 68.1% and 62.6% allowing use of MOM with recent MJ use, and 44.8% and 39.4% allowing use of MOM with ongoing use.

Of the 541 respondents who worked at a hospital with both an NICU and Level 1 nursery, 42.7% reported that their nursery had a policy in place addressing the use of MOM in the setting of MJ use in pregnancy, while 63.4% reported that their NICU had a policy in place. Of those who had a policy in place in both units, 35.8% reported that the policies were different between their Level 1 nursery and NICU.

Discussion

In the setting of recent increasing legalization of MJ and lack of evidence regarding long-term impact of newborn exposure to THC through MOM, we found that widespread variation in perinatal hospital practices focused on lactation among mothers using MJ in the prenatal and early postpartum period. Variability occurred among hospitals located within and between states with and without legalization of MJ and even between different hospital care areas within a hospital (i.e., differences in the NICU versus well baby nursery). Practices regarding support or discouragement of lactation, types of toxicology screening and requirements for abstention were particularly varied. Perinatal providers working in hospitals in REC states were more likely to report allowing MOM use with ongoing MJ use, more likely to require consent for toxicology testing, and less likely to routinely include cannabinoids on maternal and infant toxicology testing, compared with hospitals in states where MJ is illegal.

These results suggest that mothers using MJ receive differential care and support for lactation depending on the state where they deliver their infants.

Variation in perinatal practices by state legislation of MJ may be attributable to public perceptions of safety as legalization broadens; increasing prevalence of MJ use among pregnant people^18,32–34; health care provider knowledge base and perceptions; and responses by child welfare or departments of family services to positive toxicology results. Guidelines from the AAP, ACOG, and the Academy of Breastfeeding Medicine^27–29,35 all discourage MJ use with breastfeeding, although are limited in addressing methods of MJ cessation and in providing recommendations for duration of abstention. Expanding legalization does not represent scientific evidence of safety, with research demonstrating increased emergency department visits and unintentional overdoses occurring in states after MJ legalization. Alcohol and tobacco are both federally legal, despite well-documented and widely accepted known significant adverse health effects.

The intersection of legislative policy and public health³⁶ is of particular importance among certain populations who may be more susceptible to the adverse effects of MJ, such as adolescents and children, or pregnant and lactating patients and their fetuses and newborns. The variability of MJ legalization at the state level underscores the current imperative of consistency among medical professionals' organizational recommendations with respect to MJ use in the perinatal population.

In addition to variation reported among NICU policies, significant variability was reported between policies in the NICU and Level 1 nursery at individual hospitals. Infants admitted to NICUs are often premature and medically complex and may be more vulnerable to effects of THC in mother's milk. Thus, a more restrictive policy regarding use of MOM in the setting of maternal MJ use may be appropriate in the NICU, with more permissive practices in a Level 1 nursery. However, infants are frequently initially admitted to one of these units but require transfer to the other during their birth hospitalization. This need for transfer between units with different policies may result in confusion as families are exposed to differing policies at a time of stress. This represents an additional area that may result in confusion and an opportunity for consistency and clarity, both within individual hospitals and on a nationwide level.

Our study also found differences in toxicology testing among hospitals for pregnant and postpartum patients and infants, with differences in consent requirements, inclusion of cannabinoids in screening, and methods for testing. Results of toxicology testing may inform subsequent recommendations or support for lactation, in addition to implications for child protective services depending on state law. While urine toxicology testing was the most used method of infant toxicology testing, infant urine toxicology has poor sensitivity for cannabinoids,³⁷ which may lead to underreporting of exposed infants and may influence clinical decisions or opportunities for parental education. Utility of toxicology testing during the delivery hospitalization was not within the scope of this analysis.

Strengths of this study include the high number of respondents across varied disciplines working across the U.S. perinatal hospital settings. However, by using e-mail listservs of professional organizations, it is possible that individual hospitals may have been over- or underrepresented. For example, we may have included more than one individual from a single hospital who may have had different understandings of existing policies, and/or other hospitals may not have had any representation. Ideally, we would have identified a single clinical leader from each U.S. hospital that may have been able to respond regarding practices at that hospital. We considered this possibility, but to our knowledge, no such comprehensive, up-to-date contact list exists. Thus, our use of e-mail listservs matches that of other similar studies.

Because many individuals are members of more than one group surveyed and survey did not allow for completion more than one time by an individual, this survey is limited in its ability to calculate a response rate per group, and the overall response rate of 10.7% underestimates the total rate.

The AAP and other organizations recommend use of lactation support guidelines in the perinatal setting³⁵ because use of these guidelines may facilitate more standardized, consistent care and education for families. With a lack of safety data regarding optimal lactation practices among mothers using MJ, creation of evidence-based guidelines is particularly challenging. Nonetheless, use of guidelines remains important to standardize care in the setting of clinical uncertainty, if hospital teams and professional organizations can adapt guidelines over time as more evidence emerges.

Conclusions

Hospital policies and practices in the United States regarding use of MOM in the setting of MJ use during pregnancy and lactation vary widely, with significant variability between practices reported in states with and without legalized MJ, and variability between units within single hospitals. Despite the existence of policy statements from several professional organizations, variation in interpretation and state legislation has led to inconsistent practices in perinatal care. Additional research into the effects of perinatal MJ exposure and collaborative, consistent, directive guidelines across professional organizations are urgently needed to inform hospital policies.

Footnotes

Authors' Contributions

A.C.B. conceptualized and designed the study, designed the data collection instruments, collected data, coordinated and supervised data collection, drafted the original article, and critically reviewed and revised the article.

M.G.P., L.S.M., and E.M.W. conceptualized and designed the study, designed the data collection instruments, and critically reviewed and revised the article.

J.L.A. and H.S. designed the data collection instruments and critically reviewed and revised the article.

P.F.V. carried out the initial analyses and critically reviewed and revised the article.

All authors approved the final article and submitted and agree to be accountable for all aspects of the work.

Role of Funder

The Children's Miracle Network played no role in the design and conduct of this study.

Disclosure Statement

No competing financial interests exist.

Funding Information

This study was supported by an internal grant from the Children's Miracle Network Scholars' Fund, Baystate Health.

Appendix

Appendix Table A2.

State Regional Designation, Survey Respondents, and Marijuana Legal Status as of 2022 (Legal for Adult Recreational Use; Legal for Medical Use Only; Not Legal for Either Recreational or Medical Use)

State	Respondents, N (%)	Marijuana legal status (year of legislation)
Alabama	47 (1.7)	MED (2021)
Alaska	38 (1.4)	REC (2014)
Arizona	103 (3.8)	REC (2020)
Arkansas	47 (1.7)	MED (2016)
California	529 (19.7)	REC (2016)
Colorado	104 (3.9)	REC (2012)
Connecticut	47 (1.7)	REC (2021)
Delaware	26 (1.0)	MED (2011)
District of Columbia	20 (0.7)	REC (2014)
Florida	168 (6.2)	MED (2016)
Georgia	67 (2.5)	NON
Hawaii	92 (3.4)	MED (2000)
Idaho	25 (0.9)	NON
Illinois	93 (3.5)	REC (2019)
Indiana	34 (1.3)	NON
Iowa	26 (10.)	NON
Kansas	43 (1.6)	NON
Kentucky	39 (1.5)	NON
Louisiana	22 (0.8)	MED (2017)
Maine	12 (0.4)	REC (2016)
Maryland	38 (1.4)	MED (2014)
Massachusetts	60 (2.2)	REC (2016)
Michigan	52 (1.9)	REC (2018)
Minnesota	38 (1.4)	MED (2014)
Mississippi	12 (0.4)	MED (2022)^a
Missouri	33 (1.2)	MED (2018)
Montana	10 (0.4)	REC (2020)
Nebraska	17 (0.6)	NON
Nevada	17 (0.6)	REC (2016)
New Hampshire	9 (0.3)	MED (2013)
New Jersey	33 (1.2)	REC (2021)
New Mexico	23 (0.9)	REC (2021)
New York	148 (5.5)	REC (2021)
North Carolina	44 (1.6)	NON
North Dakota	10 (0.4)	MED (2016)
Ohio	67 (2.5)	MED (2016)
Oklahoma	18 (0.7)	MED (2018)
Oregon	26 (1.0)	REC (2014)
Pennsylvania	58 (2.2)	MED (2016)
Rhode Island	9 (0.3)	REC (2022)^b
South Carolina	27 (1.0)	NON
South Dakota	8 (0.3)	MED (2020)
Tennessee	29 (1.1)	NON
Texas	134 (5.0)	NON
Utah	17 (0.6)	MED (2018)
Vermont	14 (0.5)	REC (2018)
Virginia	45 (1.7)	REC (2021)
Washington	67 (2.5)	REC (2012)
West Virginia	17 (0.6)	MED (2017)
Wisconsin	24 (0.9)	NON
Wyoming	3 (0.1)	NON

Mississippi's 2022 legislation to legalize marijuana for medical use will go into effect as of late 2022.

Rhode Island's 2022 legislation took effect in March 2022, with retail sales beginning December 2022.

MED, legal for medical use only; NON, not legal for either recreational or medical use; REC, legal for adult recreational use.

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DISA Global Solutions. Map of marijuana legality by state. Available from: https://disa.com/map-of-marijuana-legality-by-state [Last accessed: March 2, 2021].

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