Return of menses

When will my periods come back?

If mothers don’t breastfeed after delivery, they will start ovulating again between 25 days and 13 weeks after delivery. The period starts two weeks after ovulation. If mothers breastfeed, their periods can be delayed for 9 to 26 months after delivery. Periods are more likely to be delayed if mothers: (a) breastfeed exclusively for the first six months, (b) breastfeed whenever the baby asks to breastfeed, (c) breastfeed at night, (d) have no long periods of separation from the baby, and (e) don’t let the baby sleep more than five hours at one time. Delaying the return of ovulation and periods prevents pregnancy and protects both mothers and babies.

A) The return of ovulation and periods

After delivery, a mother’s ovaries will start to release eggs (ovulate) again. This can result in pregnancy. If there is no pregnancy, the mother will have her period (menses) two weeks after ovulation.  

Some mothers will wait for their first period after giving birth before starting contraceptives. This can be risky as the first ovulation precedes the first period.

There are a variety of contraceptives available for breastfeeding mothers. Hormonal combination (estrogen and progesterone) birth control pills will cause periods independently of the mother’s natural cycles returning or not. Hormonal contraceptives may decrease a mother’s milk supply.

Until mothers resume ovulating, they are in a quasi-menopausal state and may experience vaginal dryness and night sweats and hot flushes.

 

B) Return of ovulation and periods if not breastfeeding

Mothers who are not breastfeeding will ovulate between 25 days and 13 weeks after delivery, with 40% ovulating by 6 weeks (Gray 1987; Jackson 2011). The periods begin two weeks after ovulation. 

C) Return of ovulation and periods if breastfeeding

1) The delay in ovulation and periods caused by breastfeeding

The return of a mother’s ovulation and periods can be delayed by breastfeeding. This delay prevents pregnancy and can be used as a type of contraception (the lactational amenorrheic method).

The mechanism for the delay is not fully understood but involves a complex interaction of hormones, the brain, and effective milk removal.

During this time, mothers may experience symptoms similar to menopause including night sweats, hot flushes, and dryness of the vagina (Marshall 1992).

2) Benefits of delaying the return of ovulation and periods

The delay in ovulation prevents pregnancy which allows the mother’s resources to be concentrated on the new baby and not shared with a new pregnancy. The delay also protects both mothers and babies as birth intervals shorter than 18 months increase the risk of (Kozuki 2013; Schummers 2018):

  • The second baby:
    • Being born small for their age.
    • Being born premature.
  • Mothers:
    • Becoming very ill.
    • Dying.

3) Optimizing breastfeeding to delay the return of ovulation and periods

Ovulation and periods may be delayed until 9 to 18 months if the mother (Gross 2002; Howie 1982; Jackson 1998):

Reports from traditional breastfeeding societies have shown a delay in the return of periods of about 26 months (Tracer 1996).

D) Early return of periods

Even if mothers are breastfeeding optimally as described above, a small number have their periods back before six months. This can cause the milk supply to decrease and their babies should be watched to make sure they are growing normally.

Mothers who allow the baby to sleep more than five hours at night or are not exclusively breastfeeding are at significantly higher risk of their periods returning.  

References

Gray RH, Campbell OM, Zacur HA, et al. Postpartum return of ovarian activity in nonbreastfeeding women monitored by urinary assays. J Clin Endocrinol Metab. 1987 Apr;64(4):645-50

Gross BA, Burger H; WHO Task Force on methods for the natural regulation of fertility. Breastfeeding patterns and return to fertility in Australian women. Aust N Z J Obstet Gynaecol. 2002 May;42(2):148-54

Howie PW, McNeilly AS, Houston MJ, et al. Fertility after childbirth: post‐partum ovulation and menstruation in bottle and breast feeding mothers. Clin Endocrinol. 1982;17:323‐332 

Jackson E, Glasier A. Return of ovulation and menses in postpartum nonlactating women: a systematic review. Obstet Gynecol. 2011 Mar;117(3):657-62
 
Jackson RL. Ecological breastfeeding and child spacing. Clin Pediatr (Phila). 1988 Aug;27(8):373-7
 
Kozuki N, Lee AC, Silveira MF, et al. The associations of birth intervals with small-for-gestational-age, preterm, and neonatal and infant mortality: a meta-analysis. BMC Public Health. 2013;13 Suppl 3(Suppl 3):S3

Marshall WM, Cumming DC, Fitzsimmons GW. Hot flushes during breast feeding? Fertil Steril. 1992 Jun;57(6):1349-50

Schummers L, Hutcheon JA, Hernandez-Diaz S, et al. Association of Short Interpregnancy Interval With Pregnancy Outcomes According to Maternal Age. JAMA Intern Med. 2018;178(12):1661–1670

Tracer DP. Lactation, nutrition, and postpartum amenorrhea in lowland Papua New Guinea. Hum Biol. 1996 Apr;68(2):277-92