THE BREASTFEEDING DYAD AND CONTRACEPTION
VICTORIA NICHOLS-JOHNSON, M.D. from BREASTFEEDING ABSTRACTS, November 2001, Volume 21, Number 2, pp. 11-12.
Women's postpartum contractive choices depend on many factors. These may include previous experience with contraceptives, future childbearing plans, husband's or partner's attitude, and the woman's lactation status. Many practitioners find that effective contraceptive use is dependent on the mother's comfort level with her choice. Ideally, contraception, like breastfeeding, is discussed with patients during the prenatal visits. In this way the patient and her partner have time to consider their options and decide what is best for them.
Lactational Amenorrhea Method (LAM)
The most common myth surrounding the use of contraception in lactating women is that lactation alone cannot be depended on to prevent pregnancy. The Lactational Amenorrhea Method (LAM) has been found to be better than 98 percent effective.(1) It has been used in a wide variety of settings, cultures, socioeconomic groups, and healthcare venues. This method is a good choice for the patient who prefers a natural method or does not want to take hormonal medication in the early months postpartum while she is exclusively nursing her baby.
Three main criteria must be met in order for LAM to be effective: 1) the baby should not be receiving any supplemental foods or artificial infant formula, 2) the baby must be less than 6 months old, and 3) the mother must not have resumed her menstrual cycle.
Ovulation in the non-lactating woman may occur as early as three weeks postpartum. The risk of ovulation in the high-frequency breastfeeding, amenorrheic woman is less than one to two percent.(2) Frequent nursing and/or pumping stimulates prolactin levels, which in turn suppress the surge of the follicle-stimulating and luteinizing hormones so that effective ovulation does not occur. Once the baby is six months old, it is more likely his diet will include foods other than human milk; he will breastfeed less and ovulation is more likely to occur.
LAM is not effective for the patient who plans to give supplemental feedings. Once the baby is over six months of age, the mother should plan on using an additional method of contraception if she wants to avoid pregnancy.
Male and female condoms and spermicides are readily available in many places over the counter. When used properly these methods can provide reliable contraception with failure rates of less than 10 percent.(3) In addition, the male condom provides some protection against sexually transmitted disease.
The advantage to barrier methods is that the mother does not ingest anything that could subsequently be secreted in her milk. The diaphragm does require fitting by a health professional, which should not be done until six weeks postpartum, when the vagina and cervix have returned to a nonpregnant state.
Controversy surrounds the use of hormonal birth control methods in breastfeeding women, particularly regarding when they should be started and whether or not combination oral contraceptives should be used. Resarch has not shown that the estrogens and progestins used in oral contraceptives (OCs) ingested by the mother are harmful to human infants, but it is known that estrogens can reduce milk supply in some women. Croxatto et al. and Peralta et al. have shown that combination oral contraceptives have a “moderate” inhibitory influence on lactation even if instituted after milk supply is well established.(4,5) Tankeyoon noted a 41.9 percent decline in milk volume with combination OCs.(6) The American College of Obstetricians and Gynecologists states that the use of combination pills is acceptable if women are informed of the risk of a decreased milk supply.(7) It is prudent to avoid their use in women who are committed to continued breastfeeding since many other choices are available.
The progestin-only oral contraceptives, injectable progestins, and progestin implants (presently unavailable in the US) have been studied and found to have no adverse effects on breastfed infants.(8,9) When to start progestin-only methods is also a cause for considerable discussion. Initiation of lactation is stimulated by the withdrawal of progesterone that occurs after delivery. Kennedy et al. suggest that one should wait at least three days before administering a progestin.(10) However, there are many anecdotal reports of milk supply being affected by the administration of a progestin-only contraceptive. Although Koetsawang noted an increase in milk supply with progestin-only contraception, Tankeyoon noted a 12 percent decline in supply with oral progestin-only contraception compared to placebo.(6,11) Waiting until at least six weeks postpartum to prescribe progestin-only contraceptives may avoid such effects.
Intrauterine devices (IUDs) currently available in the United States are the Paragard T380A and progestin-containing devices. Several other IUDs, both medicated and non-medicated, are available throughout the world. They have a failure rate of about one to two percent. Until recently, some physicians did not prescribe IUDs when a woman was breastfeeding, fearing that uterine contractions caused by oxytocin release during suckling would cause expulsion of the device. Expulsion rates are higher only if the IUD is inserted prior to four weeks postpartum.
Surgical sterilization methods are considered permanent. Male sterilization has no effect on the mother’s health or breastfeeding. Vasectomy is easier, less risky, and less expensive than female sterilization.(12) Female sterilization carries the same risks as any abdominal surgery, such as hemorrhage, infection, complications from anesthesia, and risk of injury to intraabdominal structures. Anesthetics commonly used for postpartum and interpartum female sterilization are short-acting and considered compatible with breastfeeding. Most patients will have a very short recovery time, and breastfeeding need be interrupted only during the actual surgery and time spent in the recovery room. The risk of failure ranges from 7.5/1000 to 52/1000 depending on the method used.(13)
A wide range of contraceptive choices exists for lactating women, and women may wish to consider different methods at different stages of lactation. Contraception need not interrupt or endanger the breastfeeding relationship. Mothers can be assured that effective choices are available to them at each stage of lactation and that breastfeeding can continue with confidence.
Dr. Victoria Nichols-Johnson is an Associate Professor in the Division of General Ob/Gyn at Southern Illinois University in Springfield. She is a founding member of the Academy of Breastfeeding Medicine.
1. Labbok, M. H. et al. Multicenter study of the lactational amenorrhea method (LAM): I. Efficacy, duration, and implications for clinical application. Contraception 1997; 55(6):327-36.
2. Vekemans, M. Postpartum contraception: The lactational amenorrhea method. Eur J Contracept Reprod Health Care 1997; 2(2):105-11.
3. Hatcher, R. A. et al. Contraceptive Technology, 16th rev ed. New York: Irving Publishers, 1994, table 5-2, page 113.
4. Croxatto, H. B. et al. Fertility regulation in nursing women: IV. Long-term influence of a low-dose combined oral contraceptive initiated at day 30 postpartum upon lactation and infant growth. Contraception 1983; 27(1):13-25.
5. Peralta, O. et al. Fertility regulation in nursing women: V. Long-term influence of a low-dose combined oral contraceptive initiated at day 90 postpartum upon lactation and infant growth. Contraception 1983; 27(1):27-38.
6. Tankeyoon, M. et al. Effects of hormonal contraceptives on milk volumes and infant growth. WHO Special Programme of Research, Development, and Research Training in Human Reproduction Task Force on Oral Contraceptives. Contraception 1984; 30(6):505-22.
7. Hormonal contraception. ACOG Technical Bulletin Oct 1994, page 198.
8. Chen, J. H. et al. The comparative trial of Tcu 380A IUD and progesteronereleasing vaginal ring used by lactating women. Contraception 1998 Jun; 57(6):371-79.
9. Diaz, S. et al. Fertility regulation in nursing women. IX. Contraceptive performance, duration of lactation, infant growth, and bleeding patterns during use of progesterone vaginal rings, progestin-only pills, Norplant implants, and Copper T380-A intrauterine devices. Contraception 1997; 56(4):223-32.
10. Kennedy, K. I. et al. Premature introduction of progestin-only contraceptive methods during lactation. Contraception 1997; 55(6):347-50.
11. Koetsawang, S. The effects of contraceptive methods on the quality and quantity of breast milk. Int J Gynaecol Obstet 1987; 25 Suppl:115-27.
12. Smith, G. L. et al. Comparative risks and costs of male and female sterilization. Am J Public Health 1985 Apr; 75(4):370-74.
13. Peterson, H. B. et al. The risk of pregnancy after tubal sterilization: Findings from the U.S. Collaborative Review of Sterilization. Am J Obstet Gynecol 1996 Apr; 174(4):1161-68.