Læknablaðið - 15.03.1995, Blaðsíða 34

242
LÆKNABLAÐIÐ 1995; 81
Athugun á tvíburafæðingum eftir
eðlilegan getnað og glasafrjóvgun
Þórhallur Ágústsson11, Reynir Tómas Geirsson2'
Ágústsson 1>, Geirsson RT
Obstetric outcome among naturally and IVF con-
ceived twins
Læknablaðið 1995; 81; 242-7
Pregnancy and delivery are generally perceived to
be more hazardous among twins compared to single-
tons. Assisted conception techniques have increased
the number of twins, but the effect on obstetric
management and outcome is not well known. Dur-
ing 1990-1993 there were 254 twin pregnancies of &
16 weeks gestation in Iceland, of which 52 (20.5%)
were after IVF; — a twin rate of 1:73 deliveries. The
natural rate was 1:90. IVF women were on average 3
years older but of equal height and smoking habits
as the natural mothers. Mean gestational age was 36
± 3.68 (SD) weeks for both IVF and natural twins.
In 61.9% labour commenced spontaneously after
natural conception, compared to 51.9% after IVF
(N.S.) and64.4% ofnatural and58.8% oflVFtwins
were delivered normally (N.S.). Caesarean section
rates were almost equal, but there were twice as
many forceps and ventouse deliveries of IVF babies
(p<0.02). There appeared to be a minor tendency
for more frequent elective Cesarean section in IVF
pregnancies, but emergency section was more pre-
valent among those who conceived naturally. IVF
twins were on average 64g lighter (mean birthweight
2552g) than natural twins (mean birthweight 2616g),
which was unaffected by smoking habits and ges-
tional length. The sex ratio was higher among IVF
Frá ',2) læknadeild Háskóla Islands,21 Kvennadeild Landspít-
alans. Fyrirspurnir og bréfaskriftir: Reynir Tómas Geirsson
prófessor, Kvennadeild Landspítalans, 101 Reykjavík.
Lykilorð: Twin pregnancies, in vitro fertilisation, intrauter-
ine growth.
twins. IVF twins were more often admitted to neo-
natal intensive care, but remained there a shorter
time. This suggests a lower threshold for admission
of twins conceived following IVF treatment. Per-
inatal mortality was not different among natural
compared to IVF twins; 20/1000 by conventional
criteria. Flowever when total perinatal wastage was
calculated, the figure was 46.5/1000, suggesting ex-
cess deaths early in pregnancy and beyond the first
week of life in twin pregnancies in general.
Ágrip
Tvíburameðgöngur og -fæðingar eru al-
mennt taldar áhættumeiri en einburafæðingar.
Með tilkomu tæknifrjóvgunar hefur tvíbura-
fæðingum fjölgað en lítið er vitað um áhrif þess
á meðferð og útkomu tvíburafæðinga. A tíma-
bilinu 1990-1993 voru 254 tvíburameðgöngur á
íslandi, þar sem meðgöngulengd var 16 vikur
eða meira. Af þeim voru 52 (20,5%) eftir
glasafrjóvgun. Tíðni tvíburafæðinga var í heild
1:73 en meðal eðlilega getinna tvíbura var hún
1:90. Konur sem fóru í glasafrjóvgun voru að
meðaltali þremur árum eldri en þær sem urðu
eðlilega þungaðar. Ekki var munur á líkams-
hæð eða reykingavenjum. Meðalmeðgöngu-
lengd var 36 ± 3,68 (SD) vikur hjá báðum
hópunum. Fæðing hófst eðlilega hjá 61,9%
kvenna með náttúrulega þungun og hjá 51,9%
kvenna í glasakomna hópnum (N.S.). Hjá
64,4% kvenna með náttúrulega þungun og
58,8% kvenna í glasahópnum varð eðlileg fæð-
ing. Fjöldi valinna og bráðra keisaraskurða var
svipaður þó tilhneiging hafi sést til tíðari fyrir-
fram ákveðinna keisaraskurða í glasakomna
hópnum. Inngrip í fæðingu með töng eða sog-
klukku voru algengari hjá glasafrjóvgaða
hópnunt (p< 0,02). Glasakomnu tvíburarnir
voru að meðaltali 64g léttari (meðalþyngd