Failure to initiate breastfeeding among high risk obstetrical patients who intended to breastfeed

Abstract

BACKGROUND: In the US, at the time of discharge from the hospital, 79% of women had initiated breastfeeding. Intention to breastfeed is a strong predictor of breastfeeding initiation; however, we reported initiation failure in 45% of women with pregestational diabetes who intended to breastfeed. Information regarding intention and initiation among women with other high risk obstetrical conditions (HROB) remains scarce.

OBJECTIVE: To ascertain demographic and clinical factors associated with breastfeeding initiation failure among women with HROB conditions who intended to breastfeed.

METHODS: The study population is comprised of 89 women with diabetes (DM), 57 who were receiving treatment for substance abuse (SA), 51 women diagnosed with miscellaneous (MISC) conditions and 32 with history of preterm labor/delivery (PTL/D). Intention to exclusively breastfeed or in combination with formula (breastfed/FF) was ascertained prenatally. Breastfeeding was considered initiated if at discharge ≥50% of their infant feedings were maternal milk. Statistics include chi-square, Wilcoxon’s and logistic regression (p < 0.05).

RESULTS: Of all women, 59% initiated any breastfeeding. Intention to breastfeed/FF, lack of mother-infant contact during the first hour following birth and limited lactation consultation were predictive of initiation failure. The odds of initiation failure were 2.3 times higher among women who wished to breastfeed/FF as compared to those who wished to exclusively breastfeed. Women from the SA group had lower rates of initiation failure than the other three HROB groups.

CONCLUSION: Intention to breastfeed among women with diverse HROB conditions is similar to that of the general population; however, initiation rates are disappointingly low. Intention to exclusively breastfeed results in fewer initiation failures. Prenatal intention to combine breast and formula feeding characterize women who may benefit from specific educational programs.

Keywords

Breastfeeding initiation high risk pregnancies

1 Background

Lactation is beneficial to the health of mothers and their infants [1, 2]. In the U.S. approximately 79% of the general maternal population initiated breastfeeding at the time of hospital discharge [3]. Women with high risk obstetrical (HROB) conditions and their infants may also benefit from lactation [1, 2], however their breastfeeding initiation rates lag behind those of the general population [4 –9].

Multiple cultural, social and educational factors in addition to hospital practices and maternal and neonatal medical conditions are traditionally recognized barriers to breastfeeding initiation [4 , 10–14]. Intention to breastfeed is a strong, albeit not absolute predictor of breastfeeding initiation [4, 10]. Unfortunately, women with medically and socially complex pregnancies are less likely to intend to breastfeed as compared to those without complications [5 , 12]. Recently, we reported discordance (failure) between intention to breastfeed and breastfeeding initiation in women with preeclampsia and diabetes mellitus [5–7 , 9]. However, scarce information is available on breastfeeding initiation failure among women with other HROB conditions (i.e., hypertension, obesity, substance abuse, history of preterm labor/delivery, etc.) who wish to exclusively or partially breastfeed [12 , 16]. Understanding the factors that contribute to discordance between intention to breastfeed and breastfeeding initiation is critical because, as suggested by Hundalani et al. [8], the immediate postpartum period provides an opportunity for targeted intervention.

The aim of this study was to ascertain demographic and clinical factors associated with breastfeeding initiation failure among women with HROB conditions who prenatally declared their intention to exclusively or partially breastfeed their infants.

2 Subject and methods

Our study population consisted of 229 women with HROB conditions who intended to breastfeed and who delivered infants in a single regional perinatal center during 2012–2014. In our institution, prenatal care to HROB women is provided at specialty clinics: diabetes mellitus (DM), antepartum treatment for women with substance abuse (SA), those with other miscellaneous (MISC) high risk conditions and those with a history of preterm labor/delivery (PTL/D).

This retrospective chart review was approved by the Institutional Review Board of the Wexner Medical Center at The Ohio State University. Hard copies and electronic medical records were reviewed. Pregnancies delivered ≥34 weeks of gestation and not affected by major malformations were included. Pre-pregnant body mass index (BMI, kg/m²) was defined as normal (18.5–24.9), overweight (25–29.9), obese (30–34.9), very obese (35–39.9) and extremely obese (≥40). During the first prenatal visit, women’s feeding preference for their infants was identified as exclusive breastfeeding, formula feeding (FF) or a combination of both (breastfeeding/FF) from a self-administered questionnaire on attitudes toward and prior experience with breastfeeding. Women with a history of opioid dependence currently enrolled in a treatment program and stabilized on buprenorphine/naloxone or methadone and free of human immunodeficiency virus (HIV) were encouraged to breastfeed if they also complied with the Academy of Breastfeeding Medicine (ABM) guidelines [16].

Depending on the condition of the mother and her infant following delivery, maternal-infant interactions (holding, skin to skin contact, breastfeeding) were encouraged in the delivery room and post-partum. These interactions were observed and recorded by the nurse. Per our institutional guidelines, asymptomatic infants born to HROB mothers are transferred to the well baby nursery (WBN). Our family centered care system has full time lactation consultants and rooming in available. Symptomatic infants (i.e., respiratory distress (RDS), transient tachypnea of the newborn (TTNB), hypoglycemia, birth asphyxia) are transferred directly from the delivery room to the NICU.

Infants at risk for hypoglycemia (blood glucose <40 mg/dl) are screened via serial point of care testing (Accu-Chek^®) starting at the first hour of life and prior to the first feeding [6 , 9]. Whenever possible, hypoglycemic infants in the WBN were breastfed or given formula. Those with repeated low blood glucose values were treated with IV dextrose (4–6 mg/kg/min). Lactation instruction and support was offered antenatally and postpartum to all mothers following delivery regardless of their infant feeding preference.

After delivery, neonates at risk for abstinence syndrome (NAS) were evaluated by a trained neonatal nursing staff using a modified Finnegan scale. Pharmacologic treatment with methadone was initiated if three scores ≥8 or 2 scores ≥12 were observed over a 24-hour period [17, 18].

Based on the recorded data, we defined breastfeeding initiation as either exclusive breastfeeding, formula feeding (FF) or a combination of breastfeeding (>50–99% breastmilk) and formula (breastfeeding/FF) [19]. Due to the retrospective study design, no follow-up information was available on infant feeding practices beyond hospital discharge.

3 Statistical analysis

Comparisons between groups and subgroups of patients were made with Students t-test or one way ANOVA for normally distributed continuous variables and Wilcoxon rank sum or Kruskal-Wallis tests for non-normally distributed variables; p-values for post-hoc pairwise comparisons were adjusted for multiplicity using a Bonferroni-Holm correction. All categorical variables were compared using chi squared or Fisher’s exact tests. To determine which maternal (race, parity, BMI, smoking, mode of delivery, intention to breastfeed, lactation consultation and prior breastfeeding experience) and neonatal variables (gestational age, birth weight and admission to the NICU) are independently associated with BF initiation failure among women with HROB conditions, we used multivariable logistic regression. Variable selection for all multivariable models was based on stepwise selection with an entry and exit criterion of p < 0.10. Significance was established at a two-sided p-value ≤0.05.

4 Results

The study population included 89 women (48 gestational: GDM and 41 pregestational: PGDM) in the DM, 57 in the SA, 51 in the MISC and 32 in the PTL/D group who declared their intention to breastfeed or to breastfeed/FF (Fig. 1). Analysis of demographic and clinical information showed that women in the MISC group were younger than those in the other groups. Women in the SA were 90% white, while 71% of women in the PTL/D, 49% of those in the DM and 48% in the MISC group were African American. Obesity was more common among women with DM and less common among those in the SA group. Approximately 66% of the women in the DM, SA and MISC groups and all women in the PTL/D (by definition) were multiparous. Smoking and history of perinatal infections was significantly higher among women in the SA group. Mode of delivery was also different between the groups as vaginal deliveries involved 46% DM, 60% SA, 73% MISC and 69% PTL/D. Conversely, repeat cesarean deliveries occurred in 26% DM, 18% SA, 5% MISC and 18% PTL/D. Primary cesarean deliveries affected 28% DM, 22% SA, 22% MISC and 13% PTL/D. Indications for primary cesarean deliveries were similar across the groups and included failure of labor to progress, breech presentation, suspected macrosomia, and fetal distress.

5 Diabetes mellitus

There were 48 women diagnosed with GDM; 25 were treated with a modified diet, 19 with Glyburide^® and 4 with insulin. There were 41 women with PGDM (21 class B, 5 type 2 and 15 classes C-F). Five of the 41 women with PGDM were treated with a modified diet, 4 with Glyburide^®, 5 with Metformin^® and 27 with insulin. Seventy-one of the 89 (80%) women with DM had hemoglobin A1C drawn prior to delivery (range 4.6–10.8%, median 5.9%). Besides DM, these patients had additional comorbidities including chronic hypertension (14), preeclampsia (6), obesity (27) and extreme obesity (30). Three patients had hepatitis B and four had herpes simplex virus (HSV). Seventeen (19%) of the 89 women were smokers.

6 Substance abuse treatment

This group was composed of women who remained in antepartum treatment for opiate abuse. Fifty-one of the 57 (89%) were treated with Suboxone^®, 4 with Buprenorphine^® and 2 with methadone. All of the 57 women had urine toxicology done at the time of delivery; all were positive for the prescribed substance while 2 (4%) of them were also positive for opiates. Besides the history of substance abuse, 18 of the 57 (32%) had hepatitis C and 3 (5%) had HSV. Other comorbidities included psychiatric diagnosis (4) and obesity (11) or extreme obesity (7). Forty-four (77%) of the 57 women were smokers.

7 Miscellaneous high risk obstetric conditions

Twenty-one (41%) of the 51 women cared for at this clinic were teenagers (11 ≤16 years and 10 ≥17 years). Age alone was the HROB factor for 5 (24%) of the 21 teenagers, whereas the rest had psychiatric diagnosis (4), preeclampsia (3), chronic hypertension (4), obesity (2) and (8) miscellaneous illnesses. The remaining 30 adult women attending the MISC clinic had a variety of HROB conditions including obesity (15), psychiatric illnesses (5), Graves’ disease (2), pancreatitis (1), preeclampsia (2) and (5) miscellaneous illnesses. Eight (16%) of the 51 women were smokers.

8 History of preterm labor and/or preterm delivery

The reproductive history of these 32 multiparas included 144 pregnancies that resulted in 41 (29%) term, 48 (33%) preterm deliveries, 55 (38%) abortions and 80 (60%) live children. In addition to the history of preterm labor or preterm delivery, this group of 32 patients presented with one or more comorbidities that included uterine malformations (2), preeclampsia (2), obesity (13), psychiatric illnesses (9) and STD (4). One of the 41 patients had HSV infection. Ten (31%) of the 32 women were smokers.

9 Neonatal outcomes

Of the 229 infants, 204 (89%) were born at term while the remaining 25 (11%) were born at 34 weeks (3), 35 weeks (7), or 36 weeks (15) gestation. One minute Apgar score ≤5 affected 14 of 229 (6%) infants while all 5 minute scores were greater than 6. Low and normal Apgar scores were evenly distributed among all HROB groups. One hundred and eighty-seven of the 229 infants (82%) were transferred from the delivery room to the WBN, while 42 (18%) were admitted to the NICU. Of the 89 infants born to women with DM, 23 (26%) were admitted to the NICU. Admission diagnoses were respiratory distress (9), hypoglycemia (8), prematurity (3), possible sepsis (2) and HSV infection (1). Twelve of the 57 SA (21%) were also admitted to the NICU due to respiratory distress (6), NAS (5) and r/o sepsis (1). Of the 51 infants from the MISC group the five NICU admissions (10%) were due to TTNB (2), hypoglycemia (1), birth depression (1) and possible sepsis (1). Two (6%) of the 32 infants from the PTL/D group were admitted due to TTNB.

Infants in the DM group had higher birth weight and were more likely to be admitted to the NICU as compared to those of the other HROB groups. Among infants admitted to the WBN, those in the SA group were more likely to develop NAS, have longer hospital stays and were less often discharged home with their mothers. Of the 57 infants from the SA group 21 (37%) developed NAS, five required admission to the NICU while 16 were treated in the WBN. All mothers and infants were discharged home in good health.

10 Intention to breastfeed

Intention for any breastfeeding was similar among the groups: 79% of the women in the DM, 71% in the SA, 71% in the MISC and 78% in the PTL/D group (Fig. 1). Intention to breastfeed exclusively was as follows: 35% for DM, 25% for SA, 39% for MISC and 19% for PTL/D.

11 Breastfeeding initiation failure

At the time of hospital discharge, 75 (47%) of the 158 women who intended to breastfeed/FF and 20 (28%) of the 71 who intended to exclusively breastfeed failed to initiate any breastfeeding (p = 0.007). Univariate analysis showed (Table 1) that, with the exception of intention to breastfeed/FF, mother-infant contact after birth within the first hour and lactation consultations, none of the other demographic and clinical characteristics had a statistically significant impact. The odds of breastfeeding initiation failure were 2.3 times greater among women who wished to breastfeed/FF as compared to women who wished exclusive breastfeeding.

In multivariable regression analysis, after controlling for lactation consultations, wish to exclusively breastfeed, and mother-infant contact within one hour, breastfeeding failure was 3.1 times greater among women in the DM than those from the SA group (Table 2). The other HROB groups have comparable breastfeeding failure rates.

12 Mother-infant contact during the first hour of life

Clinical and demographic characteristics of women and infants whose initial encounter was within 1 hour following birth compared to later are presented in Table 3. Women who had earlier infant contact were younger, of lower BMI and were more likely to have delivered vaginally. Breastfeeding initiation failure was 33% for 103 women with contact within the first hour, 35% for 58 women with contact 2–6 hours, 43% for 28 women with contact 7–12 hours and 73% for 40 others whose contact was >12 h (p = 0.0002).

Of the 134 mothers who delivered vaginally 77 (57%) had the first infant contact within 1 hour, 30 (22%) between 2–6 hours, 13 (10%) between 7–12 h and 14 (10%) >12 h. At the time of discharge 82 of these 134 (61%) infants initiated breastfeeding; at a similar rate to those delivered by cesarean.

Of the 42 mothers who delivered by repeat cesarean, 16 (38%) had the first contact within 1 hour, 13 (31%) between 2–6 hours, 6 (14%) between 7–12 and 7 (17%) >12 h. At the time of discharge 24 of these 42 (57%) infants initiated any breastfeeding. Repeat cesarean did not influence breastfeeding initiation failure (OR 1.183 (0.59–2.39) p = 0.6399, Table 1).

Of the 53 mothers who delivered by primary cesarean, 10 (19%) had the first infant contact within 1 hour, 15 (28%) between 2–6 hours, 11 (21%) between 7–12 h and 17 (32%) >12 h. At the time of discharge 28 of these 53 (53%) infants had initiated any breastfeeding. Primary cesarean did not influence breastfeeding initiation failure OR 1.408 (0.74–2.67) p0.2959 (Table 1).

13 Discussion

Although the rate of intention to breastfeed is similar between women with HROB conditions and the general population, breastfeeding initiation rates among HROB lag behind [5–9 , 12]. It is important to recognize that meaningful comparisons of data between studies is often precluded by vague and inconsistent definitions of breastfeeding initiation [19]. Following 1991, the WHO categorized infants as breastfed if they received “one feeding of breast milk daily or any attempt to breastfeed before discharge” [8, 14]. Others use data collected from birth certificates during the first or second day after delivery or from postpartum questionnaires provided in person, by mail or by phone, often weeks or even months following delivery [11 , 19–22]. In order to provide some consistency, a semi-quantitative, albeit arbitrary, definition based on feeding behaviors during the entire hospitalization especially at the time of discharge documented in hospital records was utilized [5–7 , 9].

Ascertaining infant feeding preference prenatally (exclusive breastfeeding, exclusive FF, or a combination of both) is important because each group of women may require a different educational approach. We have consistently reported that women with HROB conditions who declare antenatally their intention to FF seldom change their mind [5–7 , 9]. Intention to breastfeed exclusively or in combination with FF is a strong albeit not an absolute predictor of breastfeeding initiation as well as of breastfeeding continuation [5–7 , 23]. As shown in the present study, women who intended to exclusively breastfeed failed less often than those who intend to breastfeed/FF. This observation is in line with that of earlier reports [4 , 21]. Unfortunately, it would seem that intention to exclusively breastfeed is lower among women with HROB conditions or with other complex pregnancies [5–7 , 12].

Previously we reported that diabetic women were likely to intend to breastfeed, but not necessarily more likely to initiate breastfeeding [6, 7]. Possible explanations for the low breastfeeding initiation rates observed among women with PGDM include the high incidence of obesity [6, 7], cesarean delivery, complications of labor and delivery, need for specialized care of their infants, as well as delayed lactogenesis II [24]. It is also conceivable that women with PGDM may have concerns for their own health and may be more sensitive to life disruptions, such as the birth of a newborn, especially if ill [25]. Our data suggests that the discordance between intention to breastfeed and breastfeeding initiation was more pronounced among women with diabetes than among those with other HROB conditions.

Pregnant women with a history of substance abuse who wish to breastfeed may present a risk not only to themselves but also to their infants due to possible exposure to drugs, tobacco, alcohol and perinatal infections (i.e., hepatitis B and C, HIV and other sexually transmitted diseases) yet they and their infants stand to benefit significantly from lactation[15–18 , 26–28]. A pregnant HIV negative woman who intends to breastfeed should be encouraged to do so only if she complies with a comprehensive antepartum healthcare and substance abuse treatment program [15–18 , 26–28]. Another major challenge for breastfeeding in this unique group is the high incidence of NAS that often requires longer hospitalization for the infants and unavoidable mother- infant separations. In our antepartum opioid treatment program, the majority of women received Suboxone^®. While the incidence of NAS may not be affected by treatment choice, there is evidence that its severity among infants exposed to Buprenorphine^® or Suboxone^® is less than those exposed to methadone and that the need for pharmacological treatment may not be as long [26 –28]. Awareness of these observations may have encouraged some women in the SA group to intend to breastfeed.

Recently it was reported that 179 of 276 (65%) opioid dependent mothers whose infants had NAS had hepatitis C [15]. In the present investigation we noted that 29 of 78 (37%) women in the SA group had hepatitis C but, we did not find this to contribute to breastfeeding initiation failure. Breastfeeding does not appear to increase the risk of transmission because the amount of hepatitis C virus in maternal milk and colostrum is very low and is likely inactivated in the infant digestive tract [29, 30].

It has been reported that breastfeeding initiation ranged from 59–70% in late preterm infants and that breastfeeding is more problematic in late preterm infants than in term infants [31]. Difficulties associated with breastfeeding observed in late preterm infants may be due to developmental immaturities, as well as maternal morbidities directly or indirectly associated with premature birth (i.e., age, DM, obesity, pregnancy induced hypertension, cesarean deliveries) [31].

Mother-infant contact shortly after birth does not necessarily guarantee breastfeeding initiation. We, like other investigators, observed that approximately 75% of women who had contact with their babies initiated breastfeeding concurrently [32]. Our data also showed that among women who intended to breastfeed, even a significant delay in initial mother-infant contact may not necessarily lead to initiation failure. This observation is similar to an earlier report that some women with severe preeclampsia initiated breastfeeding even when they have not interacted with their infants for days [5].

Mode of delivery, in particular repeat or pre-labor cesarean delivery, is widely believed to adversely affect breastfeeding initiation or duration [33, 34]. In the present study, among women who intended to breastfeed, neither primary nor elective cesarean delivery were associated with failure to initiate breastfeeding.

Limitations of our study are the heterogeneity and size of the different HROB groups and the lack of follow-up information on infant feeding practices beyond hospital discharge. The strengths of the present investigation include the definition of breastfeeding initiation used and the fact that the data was obtained directly from hospital records and not via questionnaires from post-delivery maternal recall. More importantly is that regardless of HROB condition, these women had similar infant feeding preferences and received health care at a single institution.

14 Conclusion

Intention to breastfeed among women with diverse HROB conditions is similar to that of the general population; however initiation rates are disappointingly low. Intention to exclusively breastfeed results in fewer initiation failures. Prenatal intention to combine breast and formula feeding characterize women who may benefit from specific educational programs.

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