Methylergometrine Maleate

Derived from ergot, used in the prevention and treatment of postpartum haemorrhage. Intramuscular, intravenous or oral administration.

It is excreted in breast milk in clinically insignificant amounts ^{(Nakamichi 2012, Vogel 2004, Iwamura 1981, Erkkola 1978)} and is undetectable 6 hours after administration. ^{(Nakamichi 2012)}

Except for some product information leaflets ^{(EPhL 2024, AEMPS 2020)}, there are no reliable publications reporting problems in infants whose mothers took it, nor are they described in the English technical data sheets ^{(FDA 2012, PhF 2008)}, and it is not contraindicated during breastfeeding in the French technical data sheet. ^{(BDP 2025, ANSM 2015 and 2013)} or others. ^{(PhF 2008)} 

In infants of 29 mothers who took methylergonovine postpartum (0.125 mg twice daily for 5 days or three times daily for 3 days), there were no differences in health or neonatal development during the 17-month follow-up compared to a control group. ^{(Gilad 2017)}

There is controversy about its antiprolactin effect and its ability to decrease milk production found by some authors. ^{(Peters 1979, Dörner 1979, Weiss 1975, Pérez 1975, Shane 1974)}

A decrease in milk production (Arabin 1986) and a decrease in the duration of breastfeeding have been reported, although not in the percentage of initiation. ^{(Brown 2014, Jordan 2009)}

Others find no decrease in prolactin or milk production ^{(Gilad 2017, Moretti 2000, Javier del Castillo 1985, Jolivet 1978, Del Pozo 1975, Scapin 1983)}, nor in the rate of exclusive breastfeeding ^{(Gilad 2017)}, or weight gain at one month of age ^{(González 1984, Jolivet 1978)}, considering that treatments limited to the first week postpartum and at low doses do not affect breastfeeding or the infant.

It has frequent side effects (nausea, vomiting, headache, hypertension) that do not occur with oxytocin, which is therefore preferable for reducing the risk of postpartum haemorrhage.

Serious poisoning has occurred in newborns due to direct oral or intramuscular administration when confused with other neonatal medication ^{(Aeby 2003, Dargaville 1998)}. Careful separation of this medication from that used for neonates in delivery rooms or operating theatres is recommended. ^{(FDA 2012, Dargaville 1998)}

There is insufficient data to know whether immediate breastfeeding is effective in preventing postpartum haemorrhage ^{(Chelmow 2011)}, although immediate skin-to-skin contact after caesarean section resulted in greater uterine contraction and better maternal plasma haemoglobin levels at discharge. ^{(Pérez 2023)}