Preconception checkups being considered in Japan – recommends vitamin D above 30 ng (only 2% are above) – April 2024

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Feasibility and effectiveness of preconception check-ups at workplaces in Japan

J Occup Health. 2024 Apr 29:uiae021. doi: 10.1093/joccuh/uiae021
Akiko Fujishima 1, Eri Maeda 2, Koki Sato 3, Hidekazu Saito 4, Chihiro Ozeki 5, Yukihiro Terada 1

Objectives: Despite the recent increase in infertility and perinatal complications, preconception care is not commonly available in Japan. Working women are considered to have the greatest need for preconception care, as they increasingly marry and have children later in life. This study aimed to assess the feasibility and effectiveness of preconception check-ups in the workplace.

Methods: We provided 51 female employees aged 18-39 years with free preconception check-ups, including additional blood tests and an online medical questionnaire, during mandatory health check-ups at their workplace. A doctor provided online counselling based on the check-up results. We assessed fertility knowledge using the Cardiff Fertility Knowledge Scale (CFKS-J) and childbearing desire pre- and post-intervention.

Results: Preconception check-ups revealed various potential risk factors for future pregnancies, including underweight (12%), obesity (20%), Chlamydia trachomatis IgG antibody positivity (22%), low Rubella IgG antibody levels (47%), iron deficiency (12%), and 25-hydroxyvitamin D levels <30 ng/mL (98%). Post-intervention, the participants reported high satisfaction with the check-ups and significantly advanced their reproductive plans (P=0.008). Further, 95% of the participants indicated an intention to seek medical attention or make lifestyle changes. The post-intervention CFKS-J score (mean ± SD) was higher than the pre-intervention score (71.7 ± 19.3 versus 63.0 ± 22.0, P=0.006).

Conclusions: We developed a preconception check-up package that can be integrated into workplace health examinations, complemented by tailored counselling. This novel check-up package is a feasible and effective approach for improving preconception health and fertility awareness.
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VitaminDWiki - Pregnancy category contains

890 items in Pregnancy category

 - see also

• Overview Pregnancy and vitamin D
• Number of articles in both categories of Pregnancy and:Dark Skin 28;   Depression 21;   Diabetes 44;   Obesity 15;  Hypertension 44;   Breathing 35;  Omega-3 40;  Vitamin D Receptor 24 Click here for details
• All items in category Infant/Child 831 items
• Pregnancy needs at least 40 ng of vitamin D, achieved by at least 4,000 IU – Hollis Aug 2017
• 38+ papers with Breastfed etc, in the title
• Call to action – more Vitamin D for pregnancies, loading doses are OK – Holick Aug 2019
• 53+ preeclampsia studies
• 94+ studies with PRETERM in the title
• Fertility problem (PCOS) reduced by vitamin D: many studies 15+
• 94+ Gestational Diabetes
• Caesarean birth much more likely if low Vitamin D - many studies 15+ studies
• Post-partum depression and low Vitamin D - many studies 15+ studies
• Stillbirth reduced by Vitamin D, Zinc, Omega-3 - several studies 5+ studies
• Search VitaminDWiki for "Assisted reproduction" 33 items as of Aug 2022
• Fertility and Sperm category listing has 136 items along with related searches
• (Stunting OR “low birth weight” OR LBW) 1180 items as of June 2020
• Less labor pain if higher level of vitamin D – August 2021
• Healthy pregnancies need lots of vitamin D
• Ensure a healthy pregnancy and baby - take Vitamin D before conception
  

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VitaminDWiki – Healthy pregnancies need lots of vitamin D contains

Problem	Vit. D Reduces	Evidence
0. Chance of not conceiving	3.4 times	Observe
1. Miscarriage	2.5 times	Observe
2. Pre-eclampsia	3.6 times	RCT
3. Gestational Diabetes	3 times	RCT
4. Good 2nd trimester sleep quality	3.5 times	Observe
5. Premature birth	2 times	RCT
6. C-section - unplanned	1.6 times	Observe
Stillbirth - OMEGA-3	4 times	RCT - Omega-3
7. Depression AFTER pregnancy	1.4 times	RCT
8. Small for Gestational Age	1.6 times	meta-analysis
9. Infant height, weight, head size      within normal limits		RCT
10. Childhood Wheezing	1.3 times	RCT
11. Additional child is Autistic	4 times	Intervention
12.Young adult Multiple Sclerosis	1.9 times	Observe
13. Preeclampsia in young adult	3.5 times	RCT
14. Good motor skills @ age 3	1.4 times	Observe
15. Childhood Mite allergy	5 times	RCT
16. Childhood Respiratory Tract visits	2.5 times	RCT

RCT = Randomized Controlled Trial

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VitaminDWiki – Vitamin D greatly improves Fertility

• Vitamin D is needed for human fertility – goal is 50 ng – Sept 2018
• In-vitro Fertilization costs at least 10,000 dollars, Vitamin D costs 5 dollars
• Infertile patients 1.7X more-likely to become pregnant if take Vitamin D – meta-analysis Feb 2023
• Live birth 1.7 X more likely after IVF if good level of vitamin D – meta-analysis Aug 2020
• If diagnosed infertile, more likely to have live birth if Vitamin D fortification – Feb 2020
• Preconception vitamin D is great - every extra 10 ng associated with 10 percent more likely to have live birth – Aug 2018
• Women with more than minimum vitamin D were 3.4 X more likely to achieve pregnancy and 1.6 X more likely to have live births – June 2017
• Assisted Reproduction – 5 studies concluded vitamin D repletion helps – Review March 2015
• Pregnancy success increased 30 percent if sunny (or vitamin D) one month earlier – June 2015
• IVF 4X more successful for white women with lots of vitamin D – many studies

Increased male Vitamin D increases fertility

• Birth rates doubled with Vitamin D - 300,000 for infertile men – RCT Nov 2017
• Higher vitamin D results in 22% fewer abnormal sperm (Mendelian analysis) – May 2024
• Conception was 3.7X more likely if the male had a good level of Vitamin D – July 2022
• Far better sperm in fertility clinic if more than 30 ng of Vitamin D - June 2022
• Fertility (sperm) associated with vitamin D – meta-analysis Sept 2019
• Infertility - 71 percent of the time of BOTH partners had less than 20 ng of Vitamin D – Aug 2017
• Male fertility 4 X higher if high Vitamin D – Nov 2015
• Vitamin D somewhat assists reproduction – both the mother and the father – May 2014

Decreased Fertility if decreased Vitamin D Receptor

• Unexplained infertility 4X more likely if poor vitamin D receptor – Dec 2020
• Male Infertility is associated with poor Vitamin D Receptor – July 2021

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VitaminDWiki - 6 Pregnancy loading dose studies

This list is automatically updated

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VitaminDWiki – Consensus Vitamin D category contains:

68 Vitamin D consensus publications

• French pediatric consensus: 30 – 60 ng of Vitamin D – Feb 2022
• 15 Clinical guidelines now recommend vitamin D – Nov 2021
• 34 clinical practice Vitamin D guidelines, huge diversity – Nov 2021
• Minimum National Vitamin D recommendations range from 200 to 4,000 IU – July 2021
• Controversies and consensus in Vitamin D – 3rd Conference Sept 2019
• Vitamin D Consensus 4,000 to 10,000 IU, upper limit 100 ng – Italy 2018
• 4,000 IU of Vitamin D is OK - 19 organizations agree - 2018 six say 10,000 IU is OK
• 17 reasons why are doctors reluctant to accept vitamin D
  • Doctors and medical communities appear to be poor audiences to convince that vitamin D is good

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VitaminDWiki – Optimum category contains

The RDA is barely enough for the bones to survive.
   Need an optimal level for the body to thrive

99 items in Optimum Vitamin D category

Example pages

• Is 50 ng of vitamin D too high, just right, or not enough
• More than 30 ng of vitamin D is needed for many diseases - Feb 2022 has

• Saudi study defines normal Vitamin D level to be 50 to 70 ng (diabetes, etc.) - June 2020
• Need 40 to 60 ng of Vitamin D – 48 scientists call for action – 2015
• Vitamin D RDA of 600 IU is not enough - global RCT meta-analysis March 2019
• Vitamin D sufficiency 10 to 30 ng, optimal 40 to 80 ng (no consensus)– May 2018
• 4 X fewer visits to Dr. after getting high level of vitamin D (Interview with transcript) - Jan 3, 2022
• Vitamin D sufficiency 10 to 30 ng, optimal 40 to 80 ng (no consensus)– May 2018
• Sports benefits from up to 50 ng of Vitamin – meta-analysis - Nov 2012
• Vitamin D of 32 to 60 ng is needed before, during, and after pregnancy – Dec 2012
• Hypothesis by VitaminDWiki – Vitamin D levels are no longer limited by evolution
• VitaminDWiki pages with HIGH-DOSE in title 57 as of Feb 2022

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Note: Even more pregnancies if the male also raises his Vitamin D level