••• Chapter 22^ Lactation^227
❍ What are the three majors factors used to assess risk of maternal consumption of a drug to the
breastfed infant?
(1) Dose consumed.
(2) Oral bioavailability of the drug in both mother and infant.
(3) Elimination route and timing in both mother and infant.
❍ A mother needs to be anticoagulated postpartum. What is your drug of choice?
Coumadin is easiest for the mother and safe for the infant. Even though small quantities reach the infant, therapeutic
levels are not reached. Heparin does not get excreted into the milk but is more complicated for mother to receive.
❍ What are the recommendations of ACOG regarding use of oral contraceptives while breastfeeding?
ACOG cites that progestin-only pills and Depo-Provera do not impair lactation. Current recommendations are
to start either progestin-only pills or Depo-Provera at 6 weeks postpartum. Combined oral contraceptives have
historically not been recommended for breastfeeding women because of concerns about reduction in milk supply.
However, combined hormonal contraceptives can be used once milk supply is well established.
❍ What is the lactational amenorrhea method?
This method of family planning is advocated by the Population Council and other international groups, especially
in areas where other methods of contraception are lacking. The method requires the presence of three criteria to
reach 98% effectiveness: (1) no menses, (2) fully or nearly fully breastfeeding (ie, no solids or formula), and (3)
infant <6 months of age. At 3 months, nearly 87% are anovulatory, but this drops to 57% by 6 months. If menses
have not returned, it is felt that on the first ovulatory cycle the luteal phase is usually poor and would not sustain
implantation, making it safe to wait for menses to return before using other contraception.
❍ Can a breastfeeding mother receive postpartum rubella vaccination?
Yes.
❍ Your patient is an insulin-dependent diabetic. Can she breastfeed?
Yes. Insulin does not cross. She must watch her diet carefully but can have a very successful experience.
❍ At 4 months postpartum, your patient has an emergency appendectomy and is separated from her infant for
1 week. Her milk supply is gone on return to home. Three weeks later she calls and says her infant is having
an allergy to formulas and can she get her milk supply to return? How do you answer?
You can have her use an electric pump until her supply returns. She can slowly reintroduce the baby to the breast
in the meantime. The support of a lactation consultant during this process would be very helpful.
❍ Your patient is 2 months postpartum and has severe right lower quadrant abdominal pain? Can she have a
CT scan with contrast?
Yes. Iodinated contrast material and gadolinium-based contrast material enter breast milk at very low levels. It is
estimated that <0.01% of maternal iodinated contrast and <0.0004% of gadolinium-based contrast are absorbed
by the infant. If the patient is very concerned about exposure to her infant, she can pump and dump for 24 hours,
but she should also be allowed to nurse. There are some agents with a long elimination half-life that can be
excreted in breast milk. These should be avoided.