Polycystic ovarian syndrome and infertility

Can difficulty getting pregnant affect my milk supply?

Some mothers who have trouble getting pregnant may also have trouble breastfeeding. Those with a condition called polycystic ovarian syndrome, or PCOS, which can cause infertility, are more likely to have a low milk supply. The connection is unclear, but mothers with PCOS may have obesity, diabetes, and infrequent periods or undergo fertility treatment, all of which increase the chance of breastfeeding difficulties. Some causes of infertility do not affect breastfeeding, such as problems with the structure of reproductive organs like the uterus, fallopian tubes, or ovaries, or problems related to the father’s sperm.

A) The effect of infertility on breastfeeding

The reproductive system is controlled by various hormones that also have a role in pregnancy and lactation. Sometimes abnormalities in the levels of hormones can result in abnormal periods and difficulty in conceiving.

Some, but not all studies have reported that fertility treatment may decrease the likelihood of breastfeeding (Cromi 2015; Michels 2016; Purtschert 2020; Sha 2019) but this may be due to the increased numbers of premature births and of twins or higher multiples caused by fertility treatment (Barrera 2019).

B) Effect of polycystic ovarian syndrome on breastfeeding

Women with a condition called polycystic ovarian syndrome (PCOS), have hormonal problems which can cause infertility. They are also more likely to have a low milk supply (Marasco 2000; Vanky 2008; Vanky 2012).

The exact way PCOS affects breastfeeding is unknown. Mothers with PCOS may have one or more of the following:

  • Obesity
  • Type 2 diabetes
  • Irregular or infrequent periods
  • Infertility
  • High levels of male hormones

Both obesity and type 2 diabetes can affect breastfeeding. They may cause or contribute to breastfeeding challenges faced by mothers with PCOS (Joham 2016).

Mothers with a history of PCOS may have infrequent periods. Since the glandular tissue in the breast develops a little with each period, these mothers may have less breast tissue and, therefore, less milk.

Some mothers with PCOS are treated with the drug metformin to help them become pregnant. There is very little evidence to support using metformin to establish and increase milk production in mothers with PCOS (Vanky 2012).

C) Other causes of infertility that do not affect breastfeeding

Some mothers have difficulty getting pregnant or maintaining a pregnancy because of problems with the structure of the reproductive organs. Examples include women who have:

  • A uterus that has an abnormal structure, such as a bicornuate uterus.
  • Fallopian tubes that are blocked because of:
    • Endometriosis, a condition that causes the lining of the uterus to grow outside of it.
    • Scarring after infection.
  • Had an ovary removed.

These causes of infertility do not affect the milk supply. Similarly, infertility problems caused by the father’s sperm do not affect breastfeeding.


Barrera CM, Kawwass JF, Boulet SL, et al. Fertility treatment use and breastfeeding outcomes. Am J Obstet Gynecol. 2019 Mar;220(3):261.e1-261.e7
Cromi A, Serati M, Candeloro I, et al. Assisted reproductive technology and breastfeeding outcomes: a case-control study. Fertil Steril. 2015 Jan;103(1):89-94
Joham AE, Nanayakkara N, Ranasinha S, et al. Obesity, polycystic ovary syndrome and breastfeeding: an observational study. Acta Obstet Gynecol Scand. 2016 Apr;95(4):458-66
Marasco L, Marmet C, Shell E. Polycystic ovary syndrome: a connection to insufficient milk supply? J Hum Lact. 2000 May;16(2):143-8
Michels KA, Mumford SL, Sundaram R, et al. Differences in infant feeding practices by mode of conception in a United States cohort. Fertil Steril. 2016 Apr;105(4):1014-1022.e1

Purtschert LA, Mitter VR, Zdanowicz JA, et al. Breastfeeding following in vitro fertilisation in Switzerland - does mode of conception affect breastfeeding behaviour? Acta Paediatr. 2020 Aug 31

Sha T, Yan Y, Gao X, et al. Association of Assisted Reproductive Techniques with Infant Feeding Practices: A Community-Based Study in China. Breastfeed Med. 2019 Aug 1

Vanky E, Isaksen H, Moen MH, et al. Breastfeeding in polycystic ovary syndrome. Acta Obstet Gynecol Scand. 2008;87(5):531-5

Vanky E, Nordskar JJ, Leithe H, et al. Breast size increment during pregnancy and breastfeeding in mothers with polycystic ovary syndrome: a follow-up study of a randomised controlled trial on metformin versus placebo. BJOG. 2012 Oct;119(11):1403-9