LIPIDS

Fetal Risk Summary

Lipids (IV fat emulsions) are a mixture of neutral triglycerides, primarily unsaturated fatty acids, prepared from either soybean or safflower oil. Egg yolk phospholipids are used as an emulsifier. Most fatty acids readily cross the placenta to the fetus (1,2).

A number of reports have described the use of lipids during pregnancy in conjunction with dextrose/amino acid solutions (see Hyperalimentation, Parenteral) (3,4,5,6,7,8,9,10,11,12,13 and 14). However, one investigator concluded in 1977 that lipid infusions were contraindicated during pregnancy for several reasons: (a) An excessive increase in serum triglycerides, often with ketonemia, would result because of the physiologic hyperlipemia present during pregnancy. (b) Premature labor would occur. (c) Placental infarctions would occur from fat deposits and cause placental insufficiency (15). A brief 1986 correspondence also stated that lipids were contraindicated because of the danger of inducing premature uterine contractions with the potential for abortion or premature delivery (16). This conclusion was based on the observation that lipids contain arachidonic acid, a precursor to prostaglandins E2 and F2a (16). However, another investigator concluded that concentrations of arachidonic acid must arise from decidual membranes of amniotic fluid (i.e., must be very close to the myometrium) to produce this effect (17).

A 1986 report described four women in whom parenteral hyperalimentation was used during pregnancy, two of whom also received lipids, and, in addition, reviewed the literature for both total parenteral nutrition and lipid use during gestation (18). These authors concluded that there was no evidence that lipid emulsions had an adverse effect on pregnancy (18).

The effect of oral administration of a triglyceride emulsion on the fetal breathing index was described in a 1982 publication (19). Six women, at 32 weeks' gestation, ingested 100 mL of the emulsion containing 67 g of triglycerides and were compared with six women, also at 32 weeks' gestation, who drank mineral water. No correlation was noted between the fetal breathing index and plasma free fatty acids, glucose, insulin, glucagon, total cortisol, free cortisol, or triglyceride levels (19).

Cardiac tamponade, resulting in maternal and fetal death, has been reported in a woman receiving central hyperalimentation with lipids for severe hyperemesis gravidarum (see Hyperalimentation, Parenteral, for details of this case) (20).

A stillborn male fetus was delivered at 22 weeks' gestation from a 31-year-old woman with hyperemesis gravidarum who had been treated with total IV hyperalimentation and lipid emulsion for 8 weeks (21). The tan-yellow placenta showed vacuolated syncytial cells and Hofbauer cells that stained for fat (21). The placental fat deposits, the first to be described with parenteral lipids, were thought to be the cause of the fetal demise (21).

Based on limited clinical experience, intravenous lipids apparently do not pose a significant risk to the mother or fetus, although the case above is indicative that the therapy is not without danger. Standard precautions, as taken with nonpregnant patients, should be followed when administering these solutions during pregnancy.

Breast Feeding Summary

No reports describing the use of IV lipids during lactation have been located.

References

1. Elphick MC, Filshie GM, Hull D. The passage of fat emulsion across the human placenta. Br J Obstet Gynaecol 1978;85:610–8.
2. Hendrickse W, Stammers JP, Hull D. The transfer of free fatty acids across the human placenta. Br J Obstet Gynaecol 1985;92:945–52.
3. Hew LR, Deitel M. Total parenteral nutrition in gynecology and obstetrics. Obstet Gynecol 1980;55:464–8.
4. Tresadern JC, Falconer GF, Turnberg LA, Irving MH. Successful completed pregnancy in a patient maintained on home parenteral nutrition. Br Med J 1983;286:602–3.
5. Tresadern JC, Falconer GF, Turnberg LA, Irving MH. Maintenance of pregnancy in a home parenteral nutrition patient. JPEN 1984;8:199–202.
6. Seifer DB, Silberman H, Catanzarite VA, Conteas CN, Wood R, Ueland K. Total parenteral nutrition in obstetrics. JAMA 1985;253;2073–5.
7. Lavin JP Jr, Gimmon Z, Miodovnik M, von Meyenfeldt M, Fischer JE. Total parenteral nutrition in a pregnant insulin-requiring diabetic. Obstet Gynecol 1982;59:660–4.
8. Rivera-Alsina ME, Saldana LR, Stringer CA. Fetal growth sustained by parenteral nutrition in pregnancy. Obstet Gynecol 1984;64:138–41.
9. Di Costanzo J, Martin J, Cano N, Mas JC, Noirclerc M. Total parenteral nutrition with fat emulsions during pregnancy—Nutritional requirements: a case report. JPEN 1982;6:534–8.
10. Young KR. Acute pancreatitis in pregnancy: two case reports. Obstet Gynecol 1982;60:653–7.
11. Breen KJ, McDonald IA, Panelli D, Ihle B. Planned pregnancy in a patient who was receiving home parenteral nutrition. Med J Aust 1987;146:215–7.
12. Levine MG, Esser D. Total parenteral nutrition for the treatment of severe hyperemesis gravidarum: maternal nutritional effects and fetal outcome. Obstet Gynecol 1988;72:102–7.
13. Herbert WNP, Seeds JW, Bowes WA, Sweeney CA. Fetal growth response to total parenteral nutrition in pregnancy: a case report. J Reprod Med 1986;31:263–6.
14. Hatjis CG, Meis PJ. Total parenteral nutrition in pregnancy. Obstet Gynecol 1985;66:585–9.
15. Heller L. Parenteral nutrition in obstetrics and gynecology. In Greep JM, Soeters PB, Wesdorp RIC, et al, eds. Current Concepts in Parenteral Nutrition. The Hague:Martinus Nijhoff Medical Division, 1977:179–86.
16. Neri A. Fetal growth sustained by parenteral nutrition in pregnancy. Obstet Gynecol 1986;67:753.
17. Saldana LR. Fetal growth sustained by parenteral nutrition in pregnancy (in reply). Obstet Gynecol 1986;67:753.
18. Lee RV, Rodgers BD, Young C, Eddy E, Cardinal J. Total parenteral nutrition during pregnancy. Obstet Gynecol 1986;68:563–71.
19. Neldam S, Hornnes PJ, Kuhl C. Effect of maternal triglyceride ingestion on fetal respiratory movements. Obstet Gynecol 1982;59:640–2.
20. Greenspoon JS, Masaki DI, Kurz CR. Cardiac tamponade in pregnancy during central hyperalimentation. Obstet Gynecol 1989;73:465–6.
21. Jasnosz KM, Pickeral JJ, Graner S. Fat deposits in the placenta following maternal total parenteral nutrition with intravenous lipid emulsion. Arch Pathol Lab Med 1995;119:555–7.