This annual report - Taranaki District Health Board

Notes on InterpretationNote 1: The National Maternity Collection (MAT) contains information on selected publicly funded maternityservices from nine months before to three months after a birth. It integrates information from two data sources:LMC claims for payment for Primary Maternity Services provided under Section 88 of the NZ Public Health andDisability Act 2000; and data from the National Minimum Dataset (NMDS) on hospital admissions duringpregnancy, birth and the postnatal period for mother and baby.Up until June 2007, Section 88 claims data coverage was 95% of known births. However in July 2007, due to afunding change, DHB-employed midwifery teams ceased to submit claims to the Ministry of Health for theirservices. Thus no LMC registration data (including smoking status) is currently available in MAT for womenwho opt for DHB-based primary maternity care. In this dataset it is thus difficult to distinguish between thosewho were not registered with a LMC at the time of delivery because they accessed their primary maternity carethrough DHB services and those who received no antenatal care at all.Note 2: In this analysis, the baby’s hospital admission (birth) data from the NMDS was linked with maternalSection 88 claims data using a de-identified pregnancy key, with the unit of analysis being the baby rather thanthe mother (e.g. maternal information for twins is included twice in the analysis). Of the 129,635 babies bornduring 2009–2010, 1,113 (0.86%) were not able to be matched to their mother’s MAT record.Note 3: A relatively high proportion of babies (15.5%) had missing information on maternal smoking status atfirst LMC registration, with the majority of these babies having mothers who were not registered with a LMC.The proportion with missing information was thus not randomly distributed, but rather was higher for Pacificbabies, those with younger mothers and those from more deprived areas. Large variations between DHBswere also evident. As a result, all of the data in this section have been presented both with missing smokingstatus included and excluded from the analysis. In interpreting these data, maternal smoking rates with missingresponses included should be viewed as providing an absolute minimum estimate of the number of babieswhose mother’s smoked at first LMC registration. While maternal smoking rates with missing responsesexcluded may provide a closer approximation of the true rate, they may still be an underestimate. For example,a higher proportion of babies with younger mothers and those from more deprived areas had missing smokingstatus data, as well as higher smoking rates amongst those for whom maternal smoking status was known.Note 4: MAT does not contain details on stillborn babies as they are not assigned a NHI number at birth andare thus not reported to the National Minimum Dataset.Babies Born to Mothers Not Registered with a LMC atDeliveryNew Zealand DistributionIn New Zealand during 2009–2010, 16.2% of babies were born to mothers who were notregistered with a LMC at the time of delivery. However many of these babies’ mothers mayhave accessed hospital-based maternity services, making it difficult to estimate theproportion who received no antenatal care at all during pregnancy (Table 26).Table 26. Status of Maternal Registration with a Lead Maternity Carer at the Time ofDelivery for New Zealand Babies Born 2009–2010Maternal LMC Registration at DeliveryNo. of Babies:Total2009−2010No. of Babies:Annual AveragePercent ofBabies (%)New ZealandRegistered with a LMC 107,524 53,762 82.9Not Registered with a LMC 20,997 10,499 16.2LMC Registration Status Not Known 1,114 557 0.9Total 129,635 64,818 100.0Source: National Maternity Collection; Note: Information is for live born babies onlyNew Zealand Distribution by Maternal Age, Ethnicity and NZDep DecileIn New Zealand during 2009–2010, Pacific, Asian/Indian and Māori babies (vs. Europeanbabies) were significantly more likely to have mothers who were not registered with a LMCat delivery, as were the babies of younger mothers (less than 30 years vs. 30 or moreyears). A significantly higher proportion of babies from average to more deprived areas(NZDep06 deciles 3–10 vs. deciles 1–2) also had mothers who were not registered with aLMC at delivery (Table 27).Smoking in Pregnancy - 188