Last semester, I overhead some students talking about how Tori Spelling got pregnant one month after giving birth even though she was breastfeeding. I’ve never really understood breastfeeding-as-contraception, so I did some research about LAM, aka Lactational Amenorrhea Method.
My hope is to provide an overview of LAM to folks who are unfamiliar with this method and blew it off as just another sexual health acronym (IUD, NFP, PID, HIV, HPV, HSV, etc). If you are interested in using this method, please consult your health care provider for more detailed guidance. Check out my last blog entry Are you pregnant or parenting at UNC? for more info on resources available UNC.
What is Lactational Amenorrhea Method? Lactational Amenorrhea Method is a contraception method where a woman relies on exclusive breastfeeding to change her body’s hormonal balance to prevent pregnancy. This method can work up to the first six months of the infant’s life, which is also the duration for which the WHO and American Academy of Pediatricians recommends exclusive breastfeeding.
How does LAM work? Time to get your Anatomy & Physiology extra credit!
When a woman of reproductive age isn’t pregnant, her hypothalamus releases pulses of GnRH (gonadotropin releasing hormone). Pulses of GnRH stimulate the pituitary to release pulses of LH (luteinizing hormone) and FSH (follicle stimulating hormone). The rise & fall of LH and FSH causes the menstrual cycle. Specifically, the “LH surge” causes ovulation every month.
During pregnancy, the placenta releases estrogen & progesterone that support pregnancy and inhibit FSH and LH release, which inhibits menstruation (amenorrhea means “no period”). After delivery of the placenta, the pituitary gradually resumes the pulsing release of FSH and LH. Circulating levels rise, and eventually the menstruation resumes. Women generally start menstruating 4-6 weeks after delivery (if they don’t breastfeed), but there is variability in how long it takes before a woman is ovulating and capable of getting pregnant again. The return to fertility is unpredictable!
Women who breastfeed have a different experience. When the infant sucks on the nipple, the physical sensation signals the hypothalamus to stop releasing GnRH. No GnRH pulse, no LH pulse, no ovulation, no pregnancy. Viola! Lactational Amenorrhea Method at work.
How effective is it? If done perfectly, it can be 98% effective until the woman has a period, introduces formula, reduces frequency of feedings, or the baby reaches 6 months old.
FYI, LAM is believed to be one of the ways pregnancies get spaced when women don’t have access to other birth control methods, as is often seen in developing countries.
What do you do when LAM no longer effective? Discuss other contraception methods with a care provider. Contraception methods with estrogen (like the Pill, the Patch, and the Ring) aren’t suitable options for breastfeeding women, but progestin-only methods (like progestin-only pills, Mirena, and Implanon) or non-hormonal methods (like Paragard and condoms) are. Many breastfeeding women don’t want to use LAM, and use progestin-only or non-hormonal contraception throughout breastfeeding.
Note well that LAM provides no protection against STIs, including HIV.
If you want to read more, my main resources were Contraceptive Technology 20th Edition, Planned Parenthood , KellyMom, and Recommendations from USAID. Special thanks to Rebecca Costello for help with this blog entry!